Tracking device.



F. G. LYNDE.

TRACKING DEVICE.

APPLICATION PILED NOV. 8, 1913.

1,1 14,700. Patented Oct. 20, 1914.

WITNESSES I m/51v TOR g m. 3M4: v m. J5;

ATTORNEYS FRANK G. LYNDE, 0F NEWARK, NEW JER NEWARK, NEXV JERSEY, AFIRM.

SEY, ASSIGNOB, TO LAUTER COMPANY, OF

TRACKING DEVICE.

Specification of Letters Patent.

Application filed November 8, 1913.

Patented Oct. 20, 191-1. Serial No. 799,833.

f0 all whom it may concern Be it known that I, FRANK G. LYNDE... acitizen of the United States, residing in the city of Newark, county ofEssex, and State of New Jersey, have invented certain new and usefulimprovements in Tracking Devices, of which the following is a specification.

My invention relates to certain new and useful improvements in trackingdevices for automatically effecting lateral adjustment of the perforatedmusic sheet of a player piano to preserve the registry of itsperforations with the due of the tracker bar.

One of the prime objects of the invention is to minimize valve leakagein the control for the sheet shifting mechanism and to provide a controlwhich will instantly respond to any wandering however minute of themusic sheet while on the direct wind.

Another object of the invention is to provide a control which may hetllljllriitni rela tive to the edge of the music sheet without effectingthe valve piston or its vacuum chamber and in which all possible partsand connection are mounted in position inaccessible from the opening tothe spool box.

A still further object is to provide a noiseless sensitive movement ofthe who piston, which can be delicately balanced in inoperative positionby a part of the vacuum system of the piano.

Various other objects and advantages will be in part obvious and in partmore fully set forth in the following dcscri 'ition oi a physicalembodiment of my in vention. which consists broadly in mounting ashecthitting control valve piston casing on the out side of the spoolbox, the valve piston of which has one end in operative en mgeuicnl withthe edge of the traveling music. sheet and the opposite end cushionedagainst a flexible wall resiliently held in position by the vacuumsystem of the piano.

The invention further consists in the new and novel features ofconstruction and com bination of parts hereinafter set forth andclaimed.

Referring to the accon'ipanving draw ings ln the drawings Figure l is afront elevation of a portion of the player piano at the spool boxshowing a 'n'cferred physical embodiment of my invention; Fig. 2

is an enlarged vertical transverse sectional V such as a binding screw5?. one

outlining the end of the chamber 152.

view taken through the control shown attached to the spool 00K in Fig.1; Fig. 3 is a horizontal sectional view taken on line 3 3 of Fig. 2with parts in side elevation; and Fig. 4' is an elevation of the lefthand side of the device shown in Figs. 73 and 3.

In the drawings is show a spool box 1 within which is mounted a supplyroll 2 one end of which is mounted in the usual spring box 3 by means ofwhich the ';ertorated music sheet 4 is normally pre sed in onedirection. The sheet is drawn on to a take-up roll 5 driven by anysuitable moel'l anism and is normally in operative engage ment with theducts in the tracl-zer bar o to play the piano. The wanderings of ;hemusic sheet from its normal position on the tracker bar permits the uination of a she! shitting mechanism control 7. which con:- prises ahollow casing: is slidably mounted on pins Q. which projcctlaterallyfrom the out ide of th spool box 1 and normal to the :uljaccntedge of the traveling music sheet and lot ed by an suitable means ofwhich engaging one of the pins 9, is suiiicient to secure the casing 8.vrlve piston 10 relatively small in eross--; c('ional area extend fromthe casing; through the adja ent side of the spool box and terminznos ina sheet edge engaging head ll. The opposite erd of the prion ispositioned in a \a uun': chamber 12 termed in the casing: and bears on adiapbragnu 13 forming a pi'ieumatic cushion f rclatiwlv great pressurearea l llt vacuum chamber 1:2 is cminected bv means of the tubing ISwith some part of the vacuum system in which the vacl in is low and inwhich the va -Mun destroyed by some suitable me hanism during the re-\vl tl. The ca ing has a pair of parallel conduits ll. extending tiI\'(l'-il\ of the piston. which condu ts have unis 15 open to thatmosphere.

The piston has a rcducwl poi-lira". ll", nor mall fitting between theconduit; but adapted to be shifted due to the uandt-rii ot' the shcct toopin on or the other ot the conduits to the atniwphcrc. The conduitslead to tubing" in whi h in turn communi rates with th sheet shittingpneumatic mechanism 17 of auv conventional or suitable conslructioi'i toactuate the reach rod 1 The conduits 14 are muflled by a cacious.

tively large and inclosed and as the small 18 in one or the otherlongitudinal directions, depending upon which of the conduits It isopened by the shifted piston 10. The rod 18 has one end attached to themovable end of a pneumatic 19 forming a part of the mechanism 17 and theother end attached. to the free end of a depending lever 20, whichbears, adjacent its pivoted end, against the end of the roll drivingshaft 21, which is capable of limited longitudinal movement in itsbearing and may be moved in cooperation with the spring box 3. therequired lateral movement of the music sheet to correct its aliuementwith respect to the tracker bar 6. orous fabric 22, such as felt, whichwill 0 er but little resistance to the passage of air. A p ate 23preferably of brass covers the fabric a2 to protect the same andprovides a neat name plate.

In operation should the music sheet Wander to the left, the left conduit14 will be opened to the atmosphere, the pressure of which will actuatethe mechanism 17 to shift the lever 20 away from the end of the shaft21, permitting the spring box 3 to shift the music sheet back to itsoperative position on the tracker bar. Should the sheet Wander to theright, the opening of the other conduit 14 Will cause the lever to bearon the shaft 21 to reset the music sheet.

By means of a structure of this character, the cushioned end of thevalve piston is inclosed from the atmosphere thus minimizing leakage tothe sheet shifting valve control, but at the same time utilizing theexternal aircpressure against the diaphragm to maintain the valve pistonin cushioned conduit closing position. The pressure area of thediaphragm may be as large as desired, and the cross-section of thepiston may be as small as desired to reduce sliding friction and apolished needle slidably mounted in a close fitting hearing has beenfound efli- As the vacuum chamber is relapiston closes the valvebearing, the possibility of air leakage to this chamber is practicallyeliminated.

Mounting the control on the outside of the spool box removes from sightthe tubing and connected parts and the only element visible from theoutside of the piano is the end of the piston engaging the music sheet.Further this mounting prevents tampering with the control as it isnecessary to remove the breast board of the piano before access isafforded to the same, but by mounting the control on the pins asimplemeans of bodily adjustment is provided Without af footing theposition of the piston therein or the volume of the vacuum chamber.

It is of advantage to make the cross-section of the conduits as small aspossible which gives rise to whispering noises as the air is drawnthrough the same, but by plac ing the'i'clt covering over the conduitsthe air is multlcd and foreign noises eliminated and at the same timethe infiltration of dust to the sheet shifting pneumatic is eliminated.

Although I have shown only one form of mechanism embodying my invention,it is obvious that various changes within the skill of the mechanic maybe made therein without departing from the spirit of the invention,provided the means set forth in the following claims are employed.

Having thus described my invention, I claim 1. In a tracking device forplayer pianos. a control having a hollow space inclosed from theatmosphere, a diaphragm Wall outlining one end of said space, meansadapted to connect said space to the vacuum system of the piano wherebyto maintain said wall in a. collapsed position, a piston bearing againstsaid Wall and actuated by the wanderings of the music sheet from thenormal position of the same on the tracker bar and means controlled bythe actuation of the piston for re-setting the sheet in operativeposition relative to the tracker bar.

2. In a player piano having a tracker bar, the combination with atraveling music sheet, of mechanism actuated by the lateral wanderingsof the sheet to maintain the same in operative position relative to thetracker bar, said mechanism including pneumatics for shifting the sheetrelative to the tracker bar, a valve, a valve casing therefor, a sheetcontrolled piston having a portion Within said casing and controllingsaid pneumatics and means for maintaining said valve in inoperativeposition relative to said pneumatics, including a diaphragm controlledby a vacuum system.

3. In. a player piano having a music sheet shifting mechanism, thecombination with a member having an inclosed space, a. portion of saidspace being defined by a flexible Wall, of means for insuring a tensionwithin said space differing from the pressure on the outside of saidflexible wall, and a music sheet controlled member bearing against saidWall and controlling the sheet shifting mechanism.

4. In a player piano, the combination with a spool box, of a pinprojecting laterally from the outside of said box, a valve casingslidably mounted on said pin, a music sheet controlled piston pro}:cting from said casing through said spool box parallel to said pin andmeans for locking said casing in adjusted position.

5. In a tracking device for player pianos, a valve casing having an airconduit therethrough opened at one end to the atmosphere and connectedto sheet shifting mechanism, a sheet actuated valve for controlling saidconduit, and a muffler incompletely closing said open end of the conduitto minimize nolses caused by the air passing through said conduit.

(3.111 a player piano, the combinatioir with a conduit leading to amechanism actumin; pneumatic and adapted to be opened to the atmosphere,of a porous member ini-oinplelely closing said conduit to prevent noisecaused hy the air as it passes into said conduit.

7. in a player piano the combination with a conduit leading to amechanism actuating pneumatic and adapted to be opened to theatmosphere, of a porous member incompletely closin'r said conduittmprevent 5 whispering noises of the air as it passes into said conduitand a face plate covering said porous member to protect the same.

In witness whereof I have hereunto set my hand in the presence of twowitnesses. 20

FRANK G. LYN DE. 'itnesscs:

M. H. OBRIEN, H. R. BAUER.

